Vibration dampener



J; P. BURKE VIBRATION DAMPENER Filed April l2, 1937 Feb. 21, 1939.

INVENTOR JAMES P. BURKE ATTORNEYS mw F Patented Feb. 21', 1939 i UNITED STATES PATENT oFFlcE vnmA'rloN DAMPENER Michigan .Application April 12, 1937, Serial No. 136,459

1 Claim.

. casing and a cushion therein formed of exfoliated'vermiculite. This material is in the form of irregular. akes having a certain degree of resiliency and in mass having` a relatively high percentage of voids. when such material is combined and subjected to load it will compress and will again expand when the load is released.

l However, internal friction will retard the return formed of pressed sheetmetal having the cylin- `l movement and will also absorb energy.

As shown in Figure 1, A is a casing preferably a portion of the drical outer` wall B, a central embossed bottom portion C and a central upwardly extending tubular portion D'. E is a cover portion having the center embossed to correspond to the bottom C and having an annular flange F telescopically engaged within the cylindrical flange B. There is also a depending central tubular portion G which telescopically engages the tubular portion D.

Withthe vstructure as thus far described, the exfoliated vermiculite is placed lwithin the casing A and the cover portion E is then placed'thereon and forced downward underA an initial loadto place the vermiculite under a certain degree oi. compression. The flange BV isthen turned over the cover E, as indicated at H, to form a limiting stop therefor. l

'Ihe completed structure may be applied to various uses such as indicated in dotted lines in Figure 1 in which I is a base and J a superstructure supported thereon.- The vibration dampener is placed between these two members and is secured thereto by a bolt K passing through the central tubular portions D and G. Thus, any load on the member J which is in excess of the initial load placed on the cover E will produce a further compression of the vermiculite, the cover telescoping within the casing. If this load is varied as in the .case of shocks or vibrations, the vermiculitev will yield in response thereto, but because of internal friction will be slow in recoil. Thus, the device `forms an excellent shock absorber and vibration dampener.

-lIn Figure 3 I have shown a modified construction in which I substitute a metallic bellows L for the casing A, and an inner metallic bellows M for the tubular portion D. 'I'he space between these bellows is closed by annular bottom and .top plates `N and O which are retained by turned flanges P at the ends of the bellows. Before placing on the cover 0,' the space between the bellows is` lled with exfoliated vermiculite.

" With this structure there will be the same action but without any sliding movement ofthe metallic parts upon each other.

What I claim as my invention:

A vibration dampener comprising a casing l a stop for the outward movement 0i' said cover and holding said vermiculite under its initial compression.

JAMES P. BURKE. 

